2008 INFINITI FX35 hot

DTC P1217 ENGINE OVER TEMPERATUREEC-439
< SERVICE INFORMATION > [VQ35DE]
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CAUTION:
When a malfunction is in
dicated, be sure to replace the coolant. Refer to CO-10, "
Changing Engine
Coolant". Also, replace the engine oil. Refer to LU-7, "Changing Engine Oil".
1. Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA-10, "
Anti-Freeze Coolant Mixture Ratio".
2. After refilling coolant, run engine to ensure that no water-flow noise is emitted.
Overall Function CheckINFOID:0000000001326294
Use this procedure to check the overall function of the cooling fan. During this check, a DTC might not be con-
firmed.
WARNING:
Never remove the radiator cap when the engine is hot. Serious burns could be caused by high pres-
sure fluid escaping from the radiator.
Wrap a thick cloth around cap. Carefully remove the ca p by turning it a quarter turn to allow built-up
pressure to escape. Then turn the cap all the way off.
WITH CONSULT-III
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool befo re checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-441,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-441,
"Diagnosis Procedure".
3. Turn ignition switch ON.
4. Perform “COOLING FAN” in “ACTIVE TEST” mode with CON-
SULT-III.
5. If the results are NG, go to EC-441, "
Diagnosis Procedure".
WITH GST
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool befo re checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-441,
"Diagnosis Procedure".
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-441,
"Diagnosis Procedure".
3. Perform IPDM E/R auto active test and check cooling fan motors operation, refer to PG-20, "
Auto Active Test"
4. If NG, go to EC-441, "Diagnosis Procedure".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1217
1217 Engine over tempera-
ture (Overheat)  Cooling fan does not operate properly (Over-
heat).
 Cooling fan system does not operate proper- ly (Overheat).
 Engine coolant level was not added to the
system using the proper filling method.
 Engine coolant is not within the specified range.  Harness or connectors
(Cooling fan circuit is open or shorted.)
 IPDM E/R
 Cooling fan
 Radiator hose
Radiator
Radiator cap
 Water pump
Thermostat
For more informat ion, refer to EC-445,
"Main 12 Causes of Overheating".
SEF621W
SEF621W
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DTC P1217 ENGINE OVER TEMPERATUREEC-445
< SERVICE INFORMATION > [VQ35DE]
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Check the following.
 Harness connectors E29, E121
 Harness for open or short between cooling fan motor-2 and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK COOLING FAN MOTORS
Refer to EC-446, "
Component Inspection".
OK or NG
OK >> GO TO 13.
NG >> Replace malfunctioning cooling fan motors.
13.CHECK INTERMITTENT INCIDENT
Perform EC-139
.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-17.
NG >> Repair or replace harness or connector.
Main 12 Causes of OverheatingINFOID:0000000001326297
*1: Turn the ignition switch ON.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to CO-7
.
Engine Step Inspection item Equipment Standard Reference page
OFF 1  Blocked radiator  Blocked condenser
 Blocked radiator grille
 Blocked bumper  Visual No blocking —
2  Coolant mixture  Coolant tester 50 - 50% coolant mixture MA-10, "
Anti-Freeze
Coolant Mixture Ratio"
3  Coolant level  Visual Coolant up to MAX level in
reservoir tank and radiator
filler neckCO-10, "Changing Engine
Coolant"
4  Radiator cap  Pressure tester 59 - 98 kPa
(0.6 - 1.0 kg/cm2, 9 - 14
psi) (Limit) CO-14, "
Checking Radia-
tor Cap"
ON*25  Coolant leaks  Visual No leaks
CO-10, "Inspection"
ON*26  Thermostat  Touch the upper and
lower radiator hosesBoth hoses should be hot
CO-27
ON*17  Cooling fan  CONSULT-III Operating See trouble diagnosis for
DTC P1217 (EC-437
).
OFF 8  Combustion gas leak  Color checker chemical tester 4 Gas analyzerNegative —
ON*
39  Coolant temperature gauge  Visual Gauge less than 3/4 when
driving —
 Coolant overflow to res- ervoir tank  Visual No overflow during driving
and idling CO-10, "
Changing Engine
Coolant"
OFF*410  Coolant return from res-
ervoir tank to radiator  Visual Should be initial level in
reservoir tank CO-10, "Changing Engine
Coolant"
OFF 11  Cylinder head  Straight gauge feeler
gauge0.1 mm (0.004 in) Maxi-
mum distortion (warping) EM-101, "Removal and
Installation"
12  Cylinder block and pis-
tons  Visual No scuffing on cylinder
walls or piston EM-122
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EC-610
< SERVICE INFORMATION >[VK45DE]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is
determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from t he crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the ma ss air flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
 During warm-up
 When starting the engine
 During acceleration
 Hot-engine operation
 When selector lever is changed from N to D
 High-load, high-speed operation
 During deceleration
 During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
3
Knock sensor Engine knocking condition
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit) VDC/TCS operation command*
2
Air conditioner switch Air conditioner operation
Wheel sensorVehicle speed*
2
PBIB3020E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

ENGINE CONTROL SYSTEMEC-611
< SERVICE INFORMATION > [VK45DE]
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The mixture ratio feedback system prov
ides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst (manifold) can then better r educe CO, HC and NOx emissions. This system uses A/F
sensor 1 in the exhaust manifold to monitor whether t he engine operation is rich or lean. The ECM adjusts the
injection pulse width according to the sensor voltage si gnal. For more information about A/F sensor 1, refer to
EC-798
. This maintains the mixture ratio within the r ange of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the th ree way catalyst (manifold). Even if the switching
characteristics of A/F sensor 1 shift, the air-fuel rati o is controlled to stoichiometric by the signal from heated
oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
 Deceleration and acceleration
 High-load, high-speed operation
 Malfunction of A/F sensor 1 or its circuit
 Insufficient activation of A/F sensor 1 at low engine coolant temperature
 High engine coolant temperature
 During warm-up
 After shifting from N to D
 When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from A/F sensor 1.
This feedback signal is then sent to the ECM. The ECM cont rols the basic mixture ratio as close to the theoret-
ical mixture ratio as possible. However, the basic mi xture ratio is not necessarily controlled as originally
designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic changes dur-
ing operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value co mpared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensati on used to maintain the mixture ratio at its theoretical
value. The signal from A/F sensor 1 indicates whether the mixture ratio is RICH or LEAN compared to the the-
oretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an increase in
fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation ca rried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycl e according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all eight cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The eight fuel injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
PBIB0122E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

DTC P0101 MAF SENSOREC-761
< SERVICE INFORMATION > [VK45DE]
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DTC P0101 MAF SENSOR
Component DescriptionINFOID:0000000001326586
The mass air flow sensor is placed in
the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor c ontrols the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-III Reference Val ue in Data Monitor ModeINFOID:0000000001326587
Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000001326588
DTC Confirmation ProcedureINFOID:0000000001326589
Perform PROCEDURE FOR MALFUNCTION A first.
If DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
NOTE:
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-709
.
CAL/LD VALUE  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0101
0101 Mass air flow sensor cir-
cuit range/performance A)
A high voltage from the sensor is sent to ECM
under light load driving condition.  Harness or connectors
(The sensor circuit is open or
shorted.)
 Mass air flow sensor
 EVAP control system pressure
sensor
 Intake air temperature sensor
B) A low voltage from the sensor is sent to ECM un-
der heavy load driving condition.  Harness or connectors
(The sensor circuit is open or
shorted.)
 Intake air leaks
 Mass air flow sensor
 EVAP control system pressure sensor
 Intake air temperature sensor
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EC-768
< SERVICE INFORMATION >[VK45DE]
DTC P0102, P0103 MAF SENSOR
DTC P0102, P0103 MAF SENSOR
Component DescriptionINFOID:0000000001326595
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor controls the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current
supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326596
Specification data are reference values.
On Board Diagn osis LogicINFOID:0000000001326597
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000001326598
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR DTC P0102
1. Start engine and wait at least 5 seconds.
2. Check DTC.
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-709
.
CAL/LD VALUE  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0102
0102 Mass air flow sensor
circuit low input An excessively low voltage from the sensor is sent
to ECM.  Harness or connectors
(The sensor circuit is open or shorted.)
 Intake air leaks
 Mass air flow sensor
P0103
0103 Mass air flow sensor
circuit high input An excessively high voltage from the sensor is
sent to ECM.  Harness or connectors
(The sensor circuit is open or shorted.)
 Mass air flow sensor
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will no t rise more than 2,400 rpm due to the fuel cut.
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EC-884
< SERVICE INFORMATION >[VK45DE]
DTC P0181 FTT SENSOR
>> Repair open circuit or short to ground or short to power in harness or connector.
5.CHECK FUEL TANK TEMPERATURE SENSOR
GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “unified meter and A/C amp.” harness connector.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors B1, M11
 Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C amp.”
>> Repair open circuit or short to ground or short to power in harness or connector.
7.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-884, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace “fuel level sensor unit and fuel pump”.
8.CHECK INTERMITTENT INCIDENT
Refer to EC-717
.
>> INSPECTION END
Component InspectionINFOID:0000000001326711
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water.
Removal and InstallationINFOID:0000000001326712
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4.
Continuity should exist.
Temperature
°C ( °F) Resistance k Ω
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E
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EC-888
< SERVICE INFORMATION >[VK45DE]
DTC P0182, P0183 FTT SENSOR
3. Check harness continuity between “fuel level sensor
unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors B1, M11
 Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C amp.”
>> Repair open circuit or short to ground or short to power in harness or connector.
7.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-884, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace “fuel level sensor unit and fuel pump”.
8.CHECK INTERMITTENT INCIDENT
Refer to EC-717
.
>> INSPECTION END
Component InspectionINFOID:0000000001326718
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water.
Removal and InstallationINFOID:0000000001326719
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4.
Continuity should exist.
Temperature
°C ( °F) Resistance k Ω
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E
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